A systemic approach to moisture problems in buildings for mould safety modelling
Journal article, 2015
Mould growth in buildings can have negative consequences on health, comfort, and durability of construction
and can cause a significant problem for inhabitants. Confronted with significant uncertainty,
deterministic tools supporting design have proved insufficient for decision making. A tool that addresses
the probabilistic risk/reliability analysis of building performance is needed. A systemic approach provides
a proper theoretical base for the analysis. Based on a qualitative fault tree analysis, structure related
vulnerabilities to moisture problems have been classified at different levels of the building construction:
whole structure, component or material. A general model for evaluating the reliability of structures with
respect to mould safety and based on the concept of systemic analysis is applied to moisture problems in
buildings using a probabilistic limit state approach.
An example of a risk analysis of mould germination on the inner surface of a wooden roof panel in a
cold attic is calculated using the proposed methodology. The surface's relative humidity (given certain
surface temperature interval) is chosen as a performance aspect. The performance criteria for mould
germination on wood are also treated as a random variables. The probability of mould germination is
evaluated for different attic floor constructions in which changes to the construction were introduced on
the material or component level. The application of the probabilistic model of mould germination makes
comparisons of alternative cold attic constructions possible. Uncertainties coupled to the proposed
methodology are discussed.
Mould safety
Systemic approach
Probability
Building
Environment
Risk analysis